Prosthetic knee joint



March 29, 1949. c. v. GANOE v TAL 2,465,585

PROSTHETIC KNEE JOINT Filed Nov. 17, 1947 l, wf

INVENToRs BY M anae 4such as is provided for in prior art devices.

Patented Mar. 29, 1949 PROSTHETIC KNEE JOINT Charles V. Ganoe and Carrie M. Ganoe, El Monte, Calif.

Application November 17, 1947, Serial No. 786,423

11 Claims. (Cl. 3 2) This invention relates generally to prosthetic appliances, and more particularly to an improved prosthetic knee joint capable of being very simply locked into any selected angular position Within the normal range of angular movement of a knee joint.

It should be noted that most prior art prosthetic joints have had numerous disadvantages. For example, many such joints are incapable of .being locked in a selected position or unlocked when carrying load, which is undesirable in many circumstances. The reason for this is that many such prior art constructions have employed cam, gear, or ratchet arrangements having a plurality of teeth adapted to be engaged in a plurality of deiinite, xed positions only, and when so engaged and load applied to the joint, the friction between the engaged portions prevents disengagement of such joint until the load is re Vmoved from the joint. Furthermore, as can be seen from the above description of the general structure of such prior art joints, only a limited number of relative angular positions of the two portions of the angular joint can be assumed, which correspond to the number of engaging positions of the ratchet, gear and earn arrangement forming the joint. In addition, the locking engagement of such prior art joints is often faulty and slippage may occur with dire consequences.

A particularly important feature in a knee joint is protection and safety for an amputee wearing such a knee joint. One of the major hazards of such use of a prosthetic knee joint is that the amputee may become slightly off balance and bend the prosthetic knee slightly while considerable load is imposed thereon. If this occurs, the prosthetic knee joint may bend very rapidly and the amputee fall to the floor, which may result in serious injury. It is highly desirable, therefore, that a prosthetic knee joint capable of being very rapidly and simply locked by the amputee in the above-described circumstances be provided, so that the prosthetic knee joint may assume load and prevent the ampute from falling to the ground.

Furthermore, it is highly desirable that a knee joint be provided capable of being locked in any selected angular position within the normal operating range oi angular movement of a human knee joint. rather than being capable of taking only a certain number of angular knee positions It is also highly desirable to provide a prosthetic knee joint of a positive locking nature not prone to become disengaged or slip in the manner of prior art structures.

Generally speaking, the apparatus of the present invention comprises an upper leg knee joint member and a lower leg knee joint member pivotally attached together for limited pivotal movement in the normal range of pivotal movement of a human knee joint. Pump means is effectively, operatively connected to said knee joint members whereby relative, pivotal or angular movement therebetween will actuate said pump means in a corresponding direction. Hydraulic by-pass means is 'effectively connected between opposite ends of said pump means and includes control valve means therein adapted to control the flow of hydraulic uid from the pump means, whereby relative pivotal or angular movement of said -knee joint members actuates the pump means in a corresponding direction, pumping hydraulic fluid through said by-pass means when said valve is open'and whereby said relative, pivotal or angular movement between the knee joint members will be prevented when said valve means is closed. In the preferred form of the invention, the valve means may be arranged to be opened or closed by relative axial rotation between one of the knee joint members of the prosthetic partial leg to which it is adapted to be attached;

It can be seen from the above general description that since relative angular movement or pivotal movement of the prosthetic upper leg and the prosthetic lower leg actuate pump means, pumping hydraulic duid through a closed hydraulic system containing a control valve, closure of said valve will prevent said pump from moving and correspondingly will` prevent any further relative pivotal movement of the prosthetic upper and lower leg portions. This arrangement makes it possible to lock the knee joint in any desired position withoutthe possibility or danger of slipping or disengagement. Furthermore, the arrangement whereby the valve means may be yopened or. closed by merely slightly axially rostump slightly, which would lock .the prosthetic knee joint and the upper and lowerleg :portions v.connected thereto in a ixed position capable of carrying the full load of the amputees body,

thus preventing him from falling to the ground.

It should be further noted that this construction makes it possible to either lock or unlock the knee joint irrespective of Whether said knee joint is carrying load or not.

It should also be noted that it is possible to control the rate of relative, pivotal or angular movement of the upper prosthetic leg and the lower prostheticlegiby lpartially opening or closing the valve means and allowing the hydraulic fluid to flow therethrough at a controlled, limited rate, it being understood that as soon as the desired relative angular position is :reached the valve can then be closed, locking the knee joint in such position.

With the above points in mind, it is an object of this invention to provide anew and improved prosthetic knee joint capable of being very simply and readily locked in any selected-angular position within the normal operating range of a human knee joint.

It is a further object of this invention -tovpro- Yvide :,arnew and improved prosthetic'kneejoint .capa-ble .of zbeing vlockedpr unlocked irrespective of y.whether or l not load is'imposedon said'knee joint.

LIt is a `furtherobject of thisinventionf'topro- .vi'de anew and .improved"prostheticknee .joint which may berlockedcr unlocked 'in any angular l:position within the' normal `operating range of a human knee joint by an amputee wearing same by merely .slightlyrotating -his rlimb stump.

.Another object of the 'present `inventionsis to provide a new and improved 4prostheticknee .joint capable of angularlyrmoving from oneserl'ected angular-position to asecond'sele'cted angu- `lar` position at a controllable, angular vvelocity wwhen J-under load :andfcapablefoffbeing locked in said lselected angular-.position `upon reaching esame.

\ `Other and allied objects will-occur 'to those skilled -in -the a1'.t-uponk avcareful examination,

vstudy and perusal ofthe illustrations, specification-and vappended claims.l To'facilitate understanding, referencewill ylbefhad vto the following drawings, in which:

Fig. 1'is a diagrammatic sideelevationalview z-of `one embodiment-'of this invention.

Fig. 2 is a Vertical view in sectiontaken l:along IL-Hof Fig. 1.

Fig. 3 isa horizontal view in section taken along III-#III of'Fig. v2.

Fig. 4 isa verticalview in section taken along 'IV-IV of Fig. 2.

' More specifically, Vreferring to Figs. 1 and 2,

aprosthetic upper 'knee' joint member; indicated lgenerally'at I which is-adapted'tobe carried bya prosthetic upper leg 26, and aprosthetic Vlower kneejoint member, indicated generally at: 2 A'which is adapted to vbe carried by a vprosthetic lower leg shaft indicated at 9, -arepivotally y'joined together, as indicated generally at 3, for limited, --relativer pivotal or Y'angular -movement about the pivot point 3 VIAwithin the normal range of angu- 'lar movement of the human knee joint. 'in the example illustrated, `the --upperY -knee Ajoint mem- 4vber I' comprises a vyoke 4 having two,` parallel, downwardly exten-dingfears5 and B'which are laterally, alignedly ported as indicated 'at "l andv 3.*The lower-knee joint membenindicated at' '2 4inthe exampleillustrated; comprises alower "leg'fsliaft 19 v'and af'knee jointfshaft'l'wh'ich `is keycdito and jrota-tivel-y Afixed Iwith respect tothe "lowerileg shaft '9 `bymeans ofkey "indicated "at "I I. The knee'joint shaft I0 is rotatably carried by the ports 'I and 8 in the ears 5 and 6 and in the example shown, rotatable radial bearings I2 and I3 are positioned between the knee joint shaft 3 and the ports l and 8 in the ears 5 and 5 for reducing friction. Various other types of antifriction means may be utilized, if desired, or these may be dispensed with entirely, under certain circumstances.

Pump means, indicated generally atfI 4, is eifectively, operatively connected to or `between the upper knee joint member I' and the lower knee vjoint member 2 whereby relative, pivotal or angu- 'flar'movement between said knee joint members will actuate said pump in a corresponding direction. In the example shown, the pump means M'comprises a cylindrical housing I5 carried by .the ea-r -6 `oi the yyoke 4, which is open at the left-hand side thereof as viewed in Fig. 2, and axially receives the end of the knee joint shaft Iii therein and a radial rotor vane I6 carried by said 'kneejoint shaft I0.

"The cylindrical housing `I5 is divided into-two variable volume chambers `indicated at |"Iy and IS in Fig. 4 -by reason of theradialv rotor 4'vane I6 carried by the knee joint yshaft I0 andffby reason of the xed radial stator vane 19 extending radially inwardly rfrom the-'interior of. the housing l5 virtually'into contact with'theknee shaft I0. 'It should benoted'.1;hat` vthe-volume of the variable volume chambers I1 vand I8 may be changed by relatively rotatingjthe knee shaft "fl' -with respect to the housing I5, thus relatively rotating the rotor vaneII with vrespect'to the xed stator vane'I9 and reducing the volumeof one of said chambers while correspondingly vincreasing the vvolume of the other.v of rsaid -chambers. It should be noted' that-said chamberskr are adapted to -contain suitable hydraulic uid therein.

' By-pass-"means, indicatedfgenerallyv-at 21k-is provided for veffectively connecting oppositey Sides of the pump means I4. 'In the example shown, this comprises a conduit 2| connecting the two chambers I'I and I8. Controllable valve-means, indicated -at 22, is-providedfor effectively opening or closing the bypa'ss `means 20, thus allowing or preventing the flow of hydraulic'luid between opposite chambers I1 and I8 of the pump I4.

In theexample shown, the by-pass means `between the twochambers I1 and lI8 ,take azigezag form, as best shown in Fig. 3, and is provided with an aperture laterally vpassinggthrough the conduit 2l and indicated at 23 which, in the example shown, continues on through the housing 'in a curved arcuate path and isadapted to receive therein asimilarly'curved rod 24 of asimi- "lar, cross section which is adapted to'be attached at its opposite ends, as indicate at 25, to lthe lower end of an upper prosthetic lleg portion .26. This larrangement makes it possible .to insert, the curved rod 24 into the-similar curved ,aperture 23'and to close the'co'nduitZl between thev cham- -bers Il and i8, thus ',eifectively `closing-opposite j prosthetic upper leg portion, ,indcatedat ,25, with `-respect'to the yoke 4. This4 may bev accomplished when-the foot ofthe lowerprosthetic leg portion,

not shown, which is adapted to be attached to the lower prosthetic leg shaft 9 is resting upon the ground and the limb stump of the amputee which is adapted to be iixed with respect to the upper prosthetic leg portion 26 is axially rotated with respect thereto, thus either opening or closing the valve 22, depending upon the direction of said rotation.

It should be noted that the yoke 4 is attached to the lower end of the upper prosthetic leg portion 26 for such limited relative axial rotation at 21, thus allowing said valve actuating relative rotation. The rotatable connection between the yoke 4 and the lower end of the prosthetic leg 26, as indicated at El', comprises a bolt and nut 28, a thrust bearing 29, and a downwardly extending projection 36 carried by the lower end of the prosthetic leg portion 26 and positioned between spaced stops 3l carried by the yoke 4 which act to limit the relative axial rotation between the yoke 4 and the lower end of the prosthetic leg portion 26 to a very small angular rotation just suicient to open or close the control valve means 22.

Spring means 32 is provided for normally biasing the knee joint to a fully extended position. In the example shown this arrangement comprises the spring 32, one end of which is xed by screw means 33 to the lower end of the ear 5 of the yoke 4 and the other end of which is bent and inserted and retained in a slot 34 in the end of the knee shaft lil, thus tending to bias the knee joint in a position corresponding to an extended leg. Said biasing means is prevented from caus ing the knee joint to bend forwardly in a manner dissimilar to a human knee joint by providing stop means for limiting the relative angular movement between the prosthetic upper leg and the prosthetic lower leg. In the example shown, this stop means comprises the projections 35 and 36 carried by the ear 5 of the yoke 4 and the projection t? carried by the lower leg shaft 9 adapted to abut the projection 35 when the knee joint is in a position corresponding to a fully extended leg and adapted to abut the projection 36 when the knee joint is in fully iiexed position.

Numerous modifications and variations of the present invention within the spirit and scope hereof will occur to those skilled in the art and all such are intended to be included and comprehended herein. For example, the pump means it may assume various forms and may be connected in either direction between, and may be affixed to either of the knee joint members. The by-pass means and the control valve means may be modified in any desired manner. The structure of the yoke, knee shaft, and lower leg shaft may be modified within wide limits. The stop means for limiting relative rotation about the longitudinal axis of the leg and relative pivotal or angular movement about the lateral axis of the knee may be varied within wide limits. The spring means for normally biasing the joint into an extended position may be modified or dispensed with, if desired. The control valve means and the arrangement for actuating same may be modified within wide limits and need not necessarily be attached to the upper leg portion but may be attached to the lower leg portion, if desired.

The examples described and illustrated herein are exemplary only and are not intended to limit the scope of this invention, which is to be interpreted in the light of the prior art and appended claims only.

We claim:

1. A prosthetic knee joint, the upper end of which is arranged to be effectively fastened to a prosthetic upper leg and the lower end of which is arranged to be eilectively fastened to a prosthetic lower leg and which is adapted to be selectively locked in any desired relative, angular position within the normal range of angular movement of a human knee joint, comprising: a downwardly extending yoke member arranged for attachment to the lower end of a prosthetic upper leg for limited relative rotation about the longitudinal axis of the leg, said yoke member including two parallel, downwardly extending, laterally alignedly ported ears; a knee shaft rotatably, laterally mounted within said laterally alignedly ported ears and arranged for attachment to a prosthetic lower leg; pump means effectively, operably connected between said yoke and said knee shaft including a cylindrical, closed housing carried by the yoke and axially rotatably receiving the knee shaft; a radial rotor vane carried by said knee shaft rotatably positioned within said housing, the interior oi said housing being divided into two variable volume chambers by a fixed radial stator vane extending radially from the interior of the housing virtually into contact with the knee shaft passing through the center thereof and by the radial rotor vane carried by the knee shaft; by-pass means effectively, hydraulically connecting said two chambers; controllable valve means in said by-pass means for controlling flow of hydraulic fluid between said chambers, said pump means, bypass means and said valve means, constituting hydraulic brake arranged ior operable effective connection between a prosthetic upper leg and a prosthetic lower leg, whereby when said valve means is open, relative torque between the yoke and knee shaft will rotate said rotor Vane in a corresponding direction and increase the volume of one of said chambers and decrease the volume of the other of said chambers, and whereby said rotor rotation will be prevented when said valve means is closed, said valve means being arranged to be opened or closed by said relative limited axial rotation between the yoke and the prosthetic upper leg to which it is arranged to be attache-d; and spring means normally biasing the knee shaft and yoke into a position corresponding to a fully extended knee joint.

2. A prosthetic knee joint, the upper end of whi-ch is arranged to be effectively fastened to a prosthetic upper leg and the lower end of which is arranged to be effectively fastened to a prosthetic lower leg and which is adapted to be selectively locked in any desired relative, angular position within theA normal range of angular movement of a human knee joint, comprising: a downwardly extending yoke member arranged for attachment to the lower end of a prosthetic upper leg for limited relative rotation about the longitudinal axis of the leg, said yoke member including two parallel, downwardly extending, laterally alignedly ported ears; a knee shaft rotatably, laterally mounted within said laterally alignedly ported ears and arranged for attachment to a prosthetic lower les; pump means effectively, operably connected between said yoke and said knee shaft including a cylindrical, closed housing carried by the yoke and axially rotatably receiving the knee shaft; a radial rotor vane carried by said knee shaft rotatably positioned within said housing, the interior of said housing being divided into two variable volume chambers 1 7 by a fixed radial stator vane extending radially from the interior `of the housing virtually into contact with the knee shaft passing through the center thereof and by the radial rotor vane carried by the knee shaft; by-pass means effectively,

hydraulically connecting said two chambers; controllable valve means in said by-pass means for controlling ow of hydraulic fluid between said chambers, said pump means, by-pass means and said valve means, constituting hydraulic brake means arranged for operable effective connection between a prosthetic upper leg and a prosthetic lower leg, whereby when said valve means is open, relative torque between the yoke andlknee shaft will ro-tate said rotor vane in a corresponding direction and increase the volume of one of said chambers and decrease the volume of the other of said chambers, and whereby said rotor rotation will be prevented when said valve means is closed, said valve means being arranged to be opened or closed by said relative limited axial rotation between the yoke and the prosthetic upper leg to which it is arranged to be attached.

3. A prosthetic knee joint, the upper end of which is arranged to be effectively fastened to a prosthetic upper leg and the lower end of which is arranged to be effectively fastened to a prosthetic lower leg and which is adapted to be selectively locked in any desired relative, angular position within the normal range of angular movement of a human knee joint, comprising: a downwardly extending yoke member arranged for attachment to the lower end of a prosthetic upper leg, said yoke member including two parallel, downwardly extending, laterally alignedly ported ears; a knee .shaft rotatably, laterally mounted within said laterally alignedly ported ears and arranged for attachment to a prosthetic lower leg; pump means effectively, operably connected between said yoke and said knee shaft including a cylindrical, closed housing carried by the yoke and axially, rotatably receiving the knee shaft; a radial rotor vane carried by said knee shaft rotatably positioned within said housing, the interior of said housing being divided into two variable volume chambers by a fixed radial stator vane extending radially from the interior of the housing virtually into contact with the knee shaft passing through the center thereof and by the radial rotor vane carried by the knee shaft; by-pass means effectively hydraulically connecting said two chambers; controllable valve means in said by-pass means for controlling flow of hydraulic iuid between said chambers, said pump means, by-pass means and said valve means, constituting hydraulic brake means arranged for operable eifective connection between a prosthetic upper leg and a prosthetic lower leg, whereby when said valve means is open, relative torque between the yoke and knee shaft will rotate said rotor vane in a corresponding direction and increase the volume of one of .said chambers and decrease the volume of the other of said chambers and whereby said rotor rotation will be prevented when said valve means is closed.

A pivotally connected prosthetic knee the `upper end thereof being arranged to be effectively fastened to a prosthetic upper leg and the lower end thereof being arranged to be effectively fastened to a prosthetic lower leg and .adapted to be selectively locked in any desired relative, angular position within the normal range vofiangula-r movement of a knee joint, comprising:

a .downwardly extending yoke vmember arranged -forattachment,to the lower end jof a prosthetic upper leg for limited relative rotation aboutk the longitudinal axis of the leg, said yoke member including parallel, downwardly extending, laterally alignedly ported ears; knee shaft means rotatably, laterally mounted within said laterally alignedly ported ears and arranged for attachment to a prosthetic lower leg; hydraulic pump means oplerably effectively connected between said yoke and said knee shaft and arranged to be actuated by relative, pivotal movement therebetween; by-pass means effectively, hydraulically connecting opposite sides of said pump means; controllable valve means in said by-pass means for controlling the flow of hydraulic fluid between the opposite sides of said pump means,

whereby when said valve means is open relative torque between said knee shaft and said yoke will cause said relative, pivotal movement therebetween and will actuate Said pump means in a corresponding direction and whereby said relative, pivotal movement between the knee shaft and yoke will be prevented when said valve means is closed, said valve being arranged to be c ened or closed by said limited relative axial rotation between the yoke and a prosthetic upper leg to which. it is adapted. to be attached; and spring means normally biasing the knee shaft and yoke into a position corresponding to a fully extended knee joint.

5. A pivotally connected prosthetic knee joint, the upper end thereof being arranged to be e-ifectively fastened to a prosthetic upper leg and the lower end thereof being arranged to be effectively fastened to a prosthetic lower leg and adapted to be selectively locked in any desired relative, angular position within the normal range of angular movement of a knee joint, comprising: a downwardly extending yoke member arranged for attachment to the lower end of a prosthetic upper leg for limited relative rotation about the longitudinal axis of the leg, said yoke member including parallel, downwardly extending, laterally alienedly ported ears; knee shaft means rotatably, laterally mounted within said laterally alignedly ported ears and arranged for attachment to a prosthetic lower leg; hydraulic pump means operably, effectively connected between said yoke and said knee shaft and arranged to be actuated by relative, pivotal movement therebetween; by-pass means effectively, hydraulically connecting opposite sides of said pump means; and controllable valve means in said bypass means for controlling the flow of hydraulic fluid between the opposite sides of said pump means, whereby when said valve means is, open relative torque between said knee shaft and said yoke will cause said relative, pivotal movement therebetween and will actuate pump means a corresponding direction and whereby said relative, pivotal movement between the knee shaft and yoke will be prevented when said valve means is closed, said valve being arranged to be opened or closed by said limited relative axial rotation between the yoke and a prosthetic upper leg to which it is adapted to be attached.

6. A pivotally connected prosthetic knee joint, the upper end thereof being arranged to be effectively fastened to a prosthetic upper leg and the lower end thereof being arranged to be eectively fastened to a prosthetic lower leg and adapted to be selectively locked in any desired relative, angular position Within the normal range of angular ymovement of a knee joint,.compris ing: a downwardly extending yoke member .ar-

ranged for attachment to the lower end of a prosthetic upper leg, said yoke member including parallel, downwardly extending, laterally alignedly ported ears; knee shaft means rotatably, laterally mounted within said laterally alignedly ported ears and arranged for attachment to a prosthetic lower leg; hydraulic pump means operably, effectively connected between said yoke and said knee shaft and arranged to be actuated by relative, pivotal movement therebetween; bypass means effectively, hydraulically connecting opposite sides of said pump means; and controllable valve means in said by-pass means for controlling the now of hydraulic fluid between the opposite sides of said pump means, whereby when said valve means is open relative torque between said knee shaft and said yoke will cause said relative, pivotal movement therebetween and will actuate said pump means in a corresponding direction and whereby said relative, pivotal movement between the knee shaft and yoke will be prevented when said valve means is closed.

7. A prosthetic knee joint arranged to effectively, pivotally fasten a prosthetic upper leg and a prosthetic lower leg together and to selectively lock same in any desired relative angular position within the normal range of movement of a knee joint, comprising: an upper leg knee joint member and a lower leg knee joint member pivotally attached together for a limited range of relative pivotal movement about a lateral axis, one of said knee joint members being arranged for attachment to the end of a prosthetic partial leg for limited relative rotation about the longitudinal axis of the leg; pump means arranged to contain hydraulic fluid and be effectively, operatively connected to said knee joint members, whereby relative, pivotal movement of said knee joint members will actuate said pump in a corresponding direction; by-pass means effectively, hydraulically connecting opposite sides of said pump means; controllable valve means in said by-pass means for controlling ow of hydraulic fluid between the opposite sides of said pump means, whereby when said valve means is open relative torque between said knee joint members about said lateral axis will cause relative rotation therebetween and will actuate said pump means in a corresponding direction and whereby said relative, pivotal movement will be prevented when said valve means is closed, said valve means being arranged to be opened or closed by said relative limited axial rotation between the knee joint member and the prosthetic partial leg to which it is arranged to be attached; and means normally biasing said knee joint into a fully extended position.

8. A prosthetic knee joint arranged to effectively, pivotally fasten a prosthetic upper leg and a prosthetic lower leg together and to selectively lock same in any desired relative angular position within the normal range of movement of a knee joint, comprising: an upper leg knee joint member and a lower leg knee joint member pivotally attached together for a limited range of relative pivotal movement about a lateral axis, one of said knee joint members being arranged for attachment to the end of a prosthetic partial leg for limited relative rotation about the longitudinal axis of the leg; pump means arranged to contain hydraulic fluid and be effectively, operatively connected to said knee joint members, whereby relative, pivotal movement of said knee joint members will actuate said pump in a corresponding direction; by-pass means electively, hydraulically connecting opposite sides of said pump means; and controllable valve means in said by-pass means for controlling flow of hydraulic uid between the opposite sides of said pump means, whereby when said valve means is open relative torque between said knee joint members about said lateral axis will cause relative rotation therebetween and will actuate said pump means in a corresponding direction and whereby said relative, pivotal movement will be prevented when said valve means is closed, said valve means being arranged to be opened or closed by said relative limited axial rotation between the knee joint member and the prosthetic partial leg to which it is arranged to be attached.

9. A prosthetic knee joint comprising: an upper knee joint member and a lower knee joint member connected to each other by means -of a horizontal pivot shaft; a pump housing including a substantially cylindrical hydraulic pump chamber flxedly connected to one of said members, said pump chamber being concentric with and surrounding the end of the pivot shaft; a radial vane carried by the end of the pivot shaft within said pump chamber, said shaft being connected to the other of said joint members; a stationary radial partition in said chamber, said partition and vane dividing the pump chamber into two variable volume chambers; a by-pass conduit connecting said variable volume chambers; and a valve means in said conduit for selectively opening and closing the conduit.

10. In a prosthetic knee joint of the character stated in claim 9, the provision of a socket for the reception of the upper leg, a connection between the socket and the upper knee joint member including a vertical pivot pin and a thrust bearing, and means actuated by partial rotation of the socket with respect to the upper knee joint member for opening and closing said valve means.

11. A prosthetic knee joint of the character stated in claim 9 including cooperating stop means carried by said joint members for limiting pivotal movement of the lower knee joint member with respect to the upper joint member, and spring means biasing said pivotally connected joint members against one of said stop means.

CHARLES V. GANOE. CARRIE M. GANOE.

REFERENCES CITED UNITED STATES PATENTS Name Date Fllirppi f.- Dec. 15, 1942 vNumber 

